Bonding the UFER

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mbrooke

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I am much, much much more concerned with the outdoor located service gears potential to 'dirt' during an open neutral condition than building steel.


Once again, you sell you knowledge to short :D

You may have a valid point here, and one worth discussing. Grounding (earthing) itself can play a role in step potentials even though equal potential bonding is doing the work. Here are a few examples of what I m trying to say.


Starting at 20:43

https://www.youtube.com/watch?v=Yg6G5VUSsWA


Also another example:
 

romex jockey

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electrician
An apt post of Earthing System vulnerability Mr MBrooke.

I think perhaps the pix portrays the more extreme effects of a broken PEN , whereas the daily affair of return paths that are somehow ignored are rather telling of our grasp on Mr Kirchhoff's theories....

~RJ~
 

mbrooke

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Technician
An apt post of Earthing System vulnerability Mr MBrooke.

I think perhaps the pix portrays the more extreme effects of a broken PEN , whereas the daily affair of return paths that are somehow ignored are rather telling of our grasp on Mr Kirchhoff's theories....

~RJ~

Thanks! :)


Believe it or not TN-S and TT are the safest here, but with TN-C-S, it seems grounding and bonding must account for those down falls generated by a PEN.

Its interesting though as you point out, those parellel paths are actually what play a huge roll in safety, which ironically can also mask a broken PEN.
 

romex jockey

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electrician
Indeed so Mr MBrooke.


It may be prudent to take note of these other system configurations , if only in that they can make appearances within our own as something to challenge our earthing theory >>>>

250.36 High-Impedance Grounded Neutral Systems.
(A) Grounding Impedance Location. The grounding im-
pedance shall be installed between the grounding electrode
conductor and the system neutral point. If a neutral point is
not available, the grounding impedance shall be installed
between the grounding electrode conductor and the neutral
point derived from a grounding transformer.

~RJ~
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Indeed so Mr MBrooke.


It may be prudent to take note of these other system configurations , if only in that they can make appearances within our own as something to challenge our earthing theory >>>>



~RJ~

Good one :)

What makes this system work is equal potential bonding, and in this case actually limiting the current helps in reducing step potentials. (5 amps of fault current is less voltage drop across the EGC then 10,000 amps during a fault)
 
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